Brother,
When you are interested in a sister who has a child or children, don’t ask her what she plans to do about her children. Of course she’s a mother and she wants and needs her child to be with her. If you’re a good Muslim man, you will want to be committed to taking care of her as a wife and her children, because her family would be your family, her dependents will be your dependents.
When Prophet Muhammad proposed to Umm Salamah, she had reservations because she had little children. But listen to what the Prophet told her, “Regarding the dependent family you have mentioned, your family is my family.”
This is Sunnah. That you’re a gentleman. That you put people’s fear to ease. That you treat women with ultimate honor and respect.